Ch. 7.3 Macroevolution Flashcards
All the birds are similar to each other, what is the different part of them?
Shape of their bills
What does larger beak of bird express?
More protein BMP4 -bone morphogenic protein
When do birds with larger beaks survive better and what is the reason behind that?
Birds with larger beaks survive better in dryer season because there are larger and harder seeds to find than smaller seeds
When do birds with smaller beaks survive better and what is the reason?
Birds with smaller beaks survive better in wet season because there are many smaller seeds available
What are two rates of evolutionary changes?
Gradualism and Punctuated equilibrium
What is Gradualism?
evolutionary change that occurs extremely slowly
What is Punctuated equilibrium
how species experience long periods of little or no evolutionary change (stasis), interrupted by bursts of evolutionary change
What are 3 evidences for macroevolution?
- Fossils
- Anatomical record
- Molecular record
What are fossils?
Fossils are most direct evidence of evolution
Mostly they are bones and bones contain calcium and will not degrade by microorganisms (like rocks)
What are vertebrate embryos?
Animals that have vertebrate when they are embryos
What are two things that embryos have in common?
pharyngeal pouches (develop into gills for fish) and bony tail
What are homologous structures?
Similar physical features in organisms that share a common ancestor such as limbs of humans, cats, and whales
What are main similarities found in macromolecules of species?
Protein and DNA sequences
What is homologous molecules?
A comparison of human and mouse gene sequences which show homologous molecules
What are five factors that can alter the proportions of homozygotes and heterozygotes enough to cause evolution?
- Selection
- Mutation
- Non-random mating
- Migration
- Genetic drift
What are 3 types of natural selection?
- Directional 2. Stabilizing 3. Disruptive
What is directional selection?
Natural selection that occurs when individuals with specific trait survive and reproduce better than others
What is stabilizing selection?
Natural selection that occurs when it favors intermediate variant than the others and intermediate variants survive and reproduce better
What is disruptive selection?
Natural selection that occurs when extreme values of trait is favored than others and extreme variants survive and reproduce better
What is mutation?
Mutation is a change in a nucleotide sequence in DNA
What should mutations affect in order to be passed on to the offspring?
The mutations must affect the DNA of gametes so that it can be passed on to the offspring
When does non random mating occur?
Nonrandom mating occur when individuals prefer mates with particular ‘superior’ physical characteristics or by the preference of individuals to mate with individuals similar to themselves or prefer physical accessibility
What is migration?
Migration is the movement of individuals between populations
What are 2 factors that decides magnitude of migration effect?
- The number of migrants in the population
- The difference in allele frequency between the migrants and the
original population
